Polycarbonate lenses are widely praised for their lightweight, high impact resistance, and versatility. They are often referred to as the “safety champions” of the lens world, offering up to 10 times more impact resistance than standard plastic or glass lenses. This makes them an undisputed choice for children, athletes, and anyone with an active lifestyle. However, a common question about polycarbonate lenses is whether they are truly scratch-resistant.

In short: A raw, uncoated polycarbonate lens is indeed relatively soft and can easily be scratched. But in reality, all commercially available polycarbonate lenses come with a hard anti-scratch coating as standard.

What Are Polycarbonate Lenses?

Polycarbonate is a type of plastic known for its high impact resistance. It is made from a polymer that contains carbonate groups, which makes it both durable and lightweight. These features make polycarbonate an ideal choice for eyewear materials, especially for lenses that need to withstand daily wear and tear.

Some of the main advantages of polycarbonate lenses include:

• Lightweight: Polycarbonate lenses are much lighter than glass lenses, making them more comfortable to wear for extended periods.
• Impact Resistance: Polycarbonate lenses have excellent impact resistance, making them perfect for use in safety glasses, sports eyewear, and protective eyewear.
• UV Protection: Polycarbonate lenses naturally block 99-100% of harmful UV rays, providing built-in eye protection.
• Thin and High-Quality Optical Performance: Despite being lightweight, polycarbonate lenses can still provide excellent optical performance, making them suitable for both prescription and non-prescription eyewear.

While these advantages are clear, there is still debate surrounding the scratch resistance of polycarbonate lenses.

Why Do Some People Think Polycarbonate Lenses Aren’t Scratch-Resistant?

• Polycarbonate’s Softness

Polycarbonate is a thermoplastic polymer with long, flexible molecular chains. When hit by high-impact objects like baseballs or rocks, these chains can bend and stretch, absorbing and dissipating energy without breaking. However, this flexibility means that the surface of polycarbonate is relatively soft on the Mohs hardness scale. Sharp objects like keys, sand, or rubbing against rough surfaces can force their way between these molecular chains, causing visible scratches. In contrast, glass is much harder but lacks this flexibility, making it more prone to shattering under impact.

• Anti-Scratch Coatings

Another reason people believe polycarbonate lenses aren’t scratch-resistant is that they are prone to scratches. While polycarbonate itself is softer than other materials, most polycarbonate lenses come with an anti-scratch coating to reduce this issue. These coatings form a protective film on the lens surface, helping to enhance its scratch resistance. However, over time, these coatings may wear off, making the lenses more prone to scratching.

It’s important to note that the quality of the coating can impact its scratch resistance. High-quality anti-scratch coatings can significantly improve the durability of polycarbonate lenses, while lower-quality coatings may not offer sufficient protection.

• Comparison to Other Materials

When comparing polycarbonate lenses to glass or high-index plastic lenses, it’s often found that polycarbonate lenses perform worse in terms of scratch resistance.

Glass Lenses: Glass is much harder than polycarbonate, and therefore more resistant to scratches. However, glass lenses are heavier and more likely to break upon impact, which is why polycarbonate is often preferred for safety eyewear.

High-Index Plastic Lenses: High-index plastic lenses are made from different types of polymers and are often harder and more scratch-resistant than polycarbonate lenses. They are also thinner than regular plastic lenses, making them a popular choice for people with stronger prescriptions.

While glass and high-index lenses may perform better in terms of scratch resistance, polycarbonate lenses still offer unparalleled impact resistance, making them the top choice for safety glasses, sports eyewear, and children’s eyewear.

How to Improve the Scratch Resistance of Polycarbonate Lenses?

Although polycarbonate lenses have inherent limitations when it comes to scratch resistance, there are several ways to improve their durability and extend their lifespan.

• Hard Coating Protection: Most polycarbonate lenses come with specialized anti-scratch coatings that form a transparent, durable protective film on the lens surface, significantly enhancing scratch resistance. Choosing high-quality coatings is crucial for better durability against everyday friction and impacts.
• Proper Cleaning and Storage: Proper care is essential to keep lenses in good condition for the long term. It’s recommended to use a microfiber cloth with a professional lens cleaner to wipe lenses, avoiding cleaning agents with corrosive chemicals. When not in use, store your glasses in a hard case to prevent accidental scratches or pressure damage.
• Additional Protective Film: Some users may choose to apply a specialized protective film on the lenses. These thin, transparent films serve as an extra barrier, effectively preventing minor scratches from daily use and providing dual protection for the lenses.
• Regular Professional Checks: It’s advisable to have your eyewear checked regularly by professionals to detect potential damage early. Timely maintenance or replacement ensures that your lenses always maintain optimal optical performance and functionality.

So, are polycarbonate lenses really not scratch-resistant? The answer is not a simple “yes” or “no.” While polycarbonate lenses are softer and more prone to scratching than other materials, they are also highly popular for their lightweight and impact-resistant qualities. With the right care, high-quality coatings, and regular maintenance, the scratch resistance of polycarbonate lenses can be significantly improved.

In summary, polycarbonate lenses are not inherently “fragile,” but compared to materials like glass, they may have lower scratch resistance. However, with proper coatings and care, polycarbonate lenses can still provide long-lasting durability and maintain excellent performance.